The present invention relates to high-pressure fluid systems and particularly to attenuators or accumulators for absorbing pressure spikes in high-pressure fluid systems.
Conventional high-pressure fluid systems utilize attenuators or accumulators that absorb pressure spikes created in the system when a piston, which creates the pressure in the system, is driven back and forth. A typical attenuator or accumulator provides within the system a volume of fluid large enough to dampen pressure fluctuations present in fluid entering one end of the attenuator. The attenuator then delivers fluid from the other end of the attenuator at a more constant pressure.
The walls of high-pressure attenuators or accumulators must withstand great stresses due to internal pressure. Typical attenuators or accumulators include an accumulator body having a pressure chamber that is sealed off with a seal head coupled to an end of the accumulator body. Often the seal head is coupled to the attenuator body using fasteners that protrude into the attenuator body beyond the end of the pressure chamber. The high pressures under which high-pressure attenuators or accumulators operate, coupled with the presence of fasteners that extend into the wall of the accumulator body beyond the end of the pressure chamber, can create stress raisers within the accumulator walls causing cracks and fatigue problems.
According to the present invention, an attenuator for high-pressure system comprises a body defining a pressure chamber therein. At least one end of the body includes an opening to the pressure chamber. The attenuator also includes an engaging wall extending from the housing beyond the opening to the pressure chamber. The engaging wall defines a sealing chamber therein. A seal head is positioned within the sealing chamber and seals the opening to the pressure chamber. The seal head includes a passageway therethrough for the passage of fluid from the pressure chamber. A tensioner is threadedly coupled to the engaging wall and positioned around the passageway within the sealing chamber. A plurality of jackbolts are threaded through the tensioner and include ends contacting the seal head to bias the seal head against the opening to the pressure chamber.
In preferred embodiments, the tensioner includes threads on an outer threaded surface of the tensioner which engage mating threads on an inner threaded surface of the engaging wall. The jackbolts, threaded through the tensioner, push against a lateral face of the seal head forcing an engaging face of the seal head into engagement with a wedge surface surrounding the opening to the pressure chamber, thereby sealing the opening to the pressure chamber.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.